Catheter-directed aspiration thrombectomy and low-dose thrombolysis for patients with acute unstable pulmonary embolism: Prospective outcomes from a PE registry.

OBJECTIVES: To evaluate the efficacy and safety of aspiration thrombectomy in combination with low-dose catheter-directed thrombolysis for acute unstable pulmonary embolism (PE). BACKGROUND: Acute unstable (PE) is a life-threatening condition requiring treatment escalation, but many patients cannot receive full-dose systemic thrombolysis due to contraindications. METHODS: Eligible patients had a PE with sustained hypotension. We used a 115-cm, 8-F continuous aspiration mechanical thrombectomy catheter to perform mechanical thrombectomy, followed by catheter-directed thrombolysis with low-dose urokinase. The primary efficacy outcome was the change in the pulmonary artery pressure after aspiration thrombectomy and catheter-directed thrombolysis. Secondary efficacy outcomes were stabilization of hemodynamics post-procedure and survival to hospital discharge. The primary safety outcome was major procedure-related complications and major bleeding events. RESULTS: We included 54 patients with acute unstable PE. After thrombectomy, mean systolic pulmonary artery pressure decreased from 60.2 mm Hg to 55.2 mm Hg (P < 0.01), and to 40.5 mm Hg after catheter thrombolysis (P < 0.0001). The in-hospital PE-related death occurred in six patients (11%; 95% confidence interval [CI], 4.2-23%) at a mean follow-up of 1.1 days, and hemodynamics stabilized in the remaining 48 patients. Minor complications after thrombectomy included arrhythmias (4 of 48 patients, 8.3%; 95% CI, 2.3-20%), and minor bleeding episodes (3 of 48 patients; 6.2%; 95% CI, 1.3-17%). Major complication occurred in one patient (2.1%; 95% CI, 0.1-11%) who developed hemorrhagic transformation of paradoxical embolic stroke following catheter-directed thrombolysis. CONCLUSIONS: Aspiration thrombectomy followed by catheter-directed thrombolysis was overall effective and safe in treating patients with acute unstable PE.